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						Modified Computerized Paced Auditory Serial Addition Test (PASAT-C)
SCRIPT INFO

original PASAT.iqx Coder: Jeffrey Q. Ouyang
edited for PASAT-C by: Katja Borchert (katjab@millisecond.com) for Millisecond Software
last updated: 01-20-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 01-20-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
Script implements the PASAT-C, a modified computerized version of the Paced Auditory Serial Addition Test 
(PASAT, Gronwall 1977) based on:

Lejuez, C. W.; Kahler, Christopher W. & Brown, Richard A. (2003). A modified computer version of the Paced Auditory 
Serial Addition Task (PASAT) as a laboratory-based stressor. The Behavior Therapist, Vol 26(4), 290-293. 

The PASAT-C is a computerized distress tolerance task.
Main Differences to PASAT.iqx (by Millisecond Software):
- digits are presented visually
- the total score is onscreen the entire time
- Level 3 presents an 'escape' button
- aversive errorsound feedback

											  *Task*
Participants are presented one digit (here: 1-9) at a time. After each new digit is presented, participants are asked to 
click a response box that corresponds to the running total of the last 2 presented digits (response boxes
are presented in a circle). Participants work through 3 levels. Each level increases the speed of digit presentation.
The last level (3) provides an escape button from the task.

By design in this script: once participants start with level 1 the pacing is automatic and not under
participants' control (with the exception of the provided quitbutton during level3).


DATA FILE INFORMATION: 
The default data stored in the data files are:

(1) Raw data file: 'PASATC_raw*.iqdat' (a separate file for each participant)

build:							Inquisit build
computer.platform:				the platform the script was run on
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
blockcode, blocknum:			the name and number of the current block
trialcode, trialnum: 			the name and number of the currently recorded trial
									(Note: not all trials that are run might record data)
/currentLevel:					the currently tested level 
/currentdigit:					the currently presented digit
/currentSum:					the current correct sum
response:						the participant's response
correct:						the correctness of the response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms)

totalcorrect:					the sum of all correct responses across levels (excluding practice)
level1Correct: 					number of correct responses in level 1
level2Correct: 					number of correct responses in level 2
level3Correct: 					number of correct responses in level 3
quit:							0 = participant did NOT quit level 3; 1 = participant did quit level 3
quittime:						stores the measured duration of block 3 at time of "quitbutton" press
/level1trials -
/level3trials:					calculated trialnumbers based on level-duration and speed of digit presentation

(2) Summary data file: 'PASATC_summary*.iqdat' (a separate file for each participant)

script.startdate:				date script was run
script.starttime:				time script was started
script.subjectid:				subject id number
script.groupid:					group id number
script.elapsedtime:				time it took to run script (in ms)
computer.platform:				the platform the script was run on
/completed:						0 = script was not completed; 1 = script was completed (all conditions run)

totalcorrect:					the sum of all correct responses across levels (excluding practice)
level1Correct: 					number of correct responses in level 1
level2Correct: 					number of correct responses in level 2
level3Correct: 					number of correct responses in level 3
quit:							0 = participant did NOT quit level 3; 1 = participant did quit level 3
quittime:						stores the measured duration of block 3 at time of "quitbutton" press


EXPERIMENTAL SET-UP

digits sampled in this script: 1-9 (response boxes 1-18); digits are randomly sampled for each trial

3 levels tested that present the digits at increasing speed
Level 1: by default the digits are presented once every 3s (editable parameter) for 3 min (editable parameter)
Level 2: by default the digits are presented once every 2s (editable parameter) for 5 min (editable parameter)
!!!Note: by design Level1 automatically transitions into Level 2 WITHOUT warning (Lejuez et al, 2003)

Level 3: by default digits are presented once every 1.5s (editable parameter) for 10 min (editable parameter)
Level 3 provides an escape-button (data file stores how long Level 3 was run until escape button was pressed).
!!!Note: by design, level 2 does not transition into level 3 without warning.
However, the instruction trial for level 3 is not-selfpaced and the start of level 3 is not under participant control
(Timing for level 3 instructions are editable). 

A practice level is included. Number of practice trials as well as speed of digit presentation is editable.

Trial Sequence:
1) trial.first: presents the first digit (does not take responses) for level appropriate digit presentation time
2) level-trial: presents digit for a maximum of the level digit presentation time. If a response box is
selected before time is up, the trial is cut short and trial.isi is called for the remaining digit presentation time
3) trial.isi: interstimulusinterval -> highlights the selected box and updates the total (for
practice trials: presents feedback) for the remaining digit presentation time (then calls appropriate level-trial)
If previous response is incorrect, trial plays a short aversive sound.

STIMULI
aversive sound feedback was generated in Audacity (short noise burst for 100ms)
It can be exchanged under section EDITABLE CODE -> Editable Stimuli

!!!Note: the sizes of all visual stimuli are defined in screencanvas percentages, therefore
the size of the display depends on the size of the canvas.
Because a large display might interfere with selecting the appropriate boxes in time,
the canvassize might need to be adjusted. Go to section DEFAULTS and follow further instructions.

INSTRUCTIONS
are not original to Lejuez et al (2003) and can be edited under section INSTRUCTIONS.
Note: once the task is started with level 1, by design the pace of the task in this script is NOT
under participant's control (automatic transitions).

EDITABLE CODE:
check below for (relatively) easily editable parameters, stimuli, instructions etc. 
Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment.

The parameters you can change are:

levelCount:									number of test levels (blocks) to run. Can be 1, 2, or 3. 
practiceTrials:								number of practice trials to run (default: 11)

Timing:
NOTE: based on set block duration and set trial duration this scripts calculates the number of trials
to run in each block.
/level1duration:							duration of level1 in ms (default: 180000ms -> 3min)
/level2duration:							duration of level2 in ms (default: 300000ms -> 5min)
/level3duration:							duration of level3 in ms (default: 600000ms -> 10min)

interTrialIntervalPractice: 				interval (ms) between spoken digits during practice phase (soa - stimulus onset asynchrony)
digitpresentationtime1: 					interval (ms) between spoken digits during level 1 (default: 3000ms)
digitpresentationtime2: 					interval (ms) between spoken digits during level 2 (default: 2000ms)
digitpresentationtime3: 					interval (ms) between spoken digits during level 3 (default: 1500ms)

/ level3_instructionsduration: 				the duration of the instructions for level 3 (not-selfpaced) in ms before level 3 starts automatically. (default: 30000ms)
											Note: a timer with parameters.timerduration pops up 15s before the end of the instruction trial

/timerduration:								sets the timer duration in ms (default: 15000) 
/circleproportion:							proportion of canvas height used for the circle radius of response buttons (default: 0.4) 

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